Improvement in steam and air brakes



w. NAYLOR. l 4 Improvement in'Steam and Air Brakes. No.l l30,064.Patntedlulyao, 1872.

FIGJ.'

UNITED STATES WILLIAM NArLoE, oF MILDMAY PARK, ENGLAED.

IMPROVEMENT IN STEAM AND'AIR BRAKES.

Specification forming part of Letters Patent No. 130,064, dated July 30,18752.

SPECIFICATION.

I, WILLIAM NAYLOR, of Mildmay Park, in the county of Middlesex, England,engineer,

have invented Improvements in Railway Brakes and in apparatus connectedtherewith, of which the following is a specification:

This invention relates to that class of coutinuousaction brakes forrailway carriages wherein the power of a spring, in combination withtoggle-links, is employed for applying the brakes, and the direct forceof steam, air, or water is employed for taking off the brakes; andconsists of certain improvements, hereinafter described, in theconstruction and arrangement of such brakes, and of the mechanicalappliances requisite for working the same.

Figure l of my drawing represents a lon gitudinal sectional elevation ofmy improved arrangement of continuous brake for railway carriages,lwherein the spring acts by its contractile strain; and Fig. 2 is acorresponding plan of thesame.

A represents the carriage-frame, and B B the Wheels. C is theweighTs'haft, supported at each end. in brackets bolted to the framing,and having keyed or otherwise secured to the "center thereof, so as tobe in the longitudinal center line of the carriage, the double or par-'allel brake-lever D. This lever D carries a grooved pulley, E, at itsextremity, under which and over two other xed pulleys, F F, passes thecontinuous rope or chain G, which extends throughout the train, andwhose function is to maintain the several brake-levers D elevated andthe brakes oft To the free end of the brake-lever there are jointed thepair of toggle-joint links H, one end working on'a fixed center at I inthe main framing. To the center jointK of' these links H there areconnected the side links L L and central helical spring M, the extremityof the latter being adjustably connected to a bracket, N, secured to themain framing. This spring op.-` erates by its contraction to put on thebrakes, the pull upon the center joint at K tending to p straighten thetogglejoint links and force down the brake-lever in connectiontherewith, thereby applying the brakes so soon as the continuous rope orchain G is released or slackencd= sufficiently the same operation takesplace simultaneously, or nearly so, throughout the whole of the brakesof the series. rThe brake-levers act upon the brakes through theweigh-shaft G, short lever-arms O O', and rods P P', which latter areconnected to the transverse tie-rods Q Q', suspended in the links R It',and carrying the pairs of brake-blocks S S'. These blocks are bypreferenceV composed of cast-iron, and are made reversible-that is tosay, they are free to turn on the rods Q Q', so that when one face-of abrake block becomes worn the other can be brought into operation.

When the brakes are to be taken oft` the rope or chain is hauled uponeither by the direct action of steam, compressedair, or Water pressure,as hereinafter fully described, whereupon the several brake-applyingsprings will be again brought to a state of tension or compression, asthe case may be, and the brakelevers elevated and maintained in thatcondition by the tension of the continuous rope or chain until thebrakes are required to be again applied. If preferred, the weigh-shaftC, in lieu of being situate near the end of the framing, as shown inFig. l, may be placed between the wheels, and transmit motion to thebrakesby an arrangement of links and pushrods., similar to that shown inmy specification No. l. Figs. 3 and 4 represent two sectionalelevations, taken at right angles, the one to the other, of an improvedarrangement of direct-acting steam, compressed-air, or hydraulic lifterfor hauling in the continuous rope or chain, with a view to lifting ortaking off the brakes of railway trains, and maintaining or supportingsuch brakes out of action until required for application. A liftersimilar to this is intended to be placed at one or both ends of thetrain-namely, in the brake-van or in the brake-van and on the engine. AA are two steam-cylinders, B B are pistons working therein, connected bytheir rods C C to the common cross-head D, which works between thestationary slotted guides E E. To one end of these guides there arefitted one or more stationary pulleys, F F, correspondingtraversing-pulleys H H being connected by the links I I with thecross-head D. G is the continuous rope or chain already referred to, andillustrated in Figs. 1 and 2, which is iutended for lifting oft thebrakes and maintaining these clear of the wheels. This chain G has oneend secured to a fixed point, K, an d is passed round the pulleys H andF, and thence passes underneath the carriages Valong the center of thetrain, so as to be connected with the several brake-levers in the mannershown in Figs. l and 2. So long as steam from the boiler is admittedunderneath the pistons of the lifter by the orifice Ii the cross-headcarrying the pulleys H will be elevated or moved to the extremity of itsguides, and will thereby maintain the rope or chain G hauled taut andthebrakes lifted off. On allowing the steam to escape from the cylindersofthe lifter the several helical springs and toggle-joint levershereinbefore referred to are permitted to come into action and apply thebrakes, the piston of the lifter being left free to be drawn, by theropeor chain G, to the opposite end of the cylinders as the said chain isrun out by the descent of the several brake-levers. As it would beobjectionable to allow the pistons to strike the end of the cylinders Ipropose to leave a suflicient quantity of steam confined within thecylinder to form a cushion which shall arrest the motion of the pistonsgradually and gently during the putting on of the brakes. To accomplishthis I have a valve, M, Fig. 5, in the pipe or passage N, through whichthe steam enters the lifter and escapes therefrom as required, as Ishall presently explain. This valve allows free ingress of steam to thelifter, and is also kept open against the current of exhaust steam whenthe communication with the boiler is shut off; but just before thepistonsreach the end of their cylinders the valve is closed, so as tocheck all further escape, Vby meansv of the levers O I) and rod Q, thelever O being struck by the cross-head D, transmitting its motion to thelever P, which closes the valve M. Fig. 6 represents an improvedarrangement of three-way cock which I employ for the purpose of takingoff and putting on the brakes, as above described. N N are two branches,either one of which leads to the lifter and corresponds to the branch Ncontaining the cushion-valve shown in Fig. 5, while the other opensdirect to the atmosphere. This cock is situated on the engine, andcommunicates, by the branch-pipe C, with the boiler through an improvedpressure-regulator, which I shall presently describe. If the engine bechanged from one end of the train to the other the respective functionsof the two branches N and N of the cock will also be reversedthat is tosay, the one which was previously connected by a pipe extending alongthe train to the lifter will be left open to the atmosphere as an escapeor exhaust, while the other branch, which previously served as anescape, will form the connection with the lifter. D is the plug of thecock, made hollow and provided with three openings, a, a', and c. InFig. 6 the plug is shown in the position in which it is to be turnedwhen the brakes are to be applied that is to say, with the branch Gclosed and the steam from the boiler shut oif, while the escape from thelifter cylinder or cylinders is fully open through the openings a n andbranches N N, as shown by the arrow. Now, by a mere quarter of a turnofthe plug D the steam can be admitted again into the lifter through thebranch N or N', as the case may be, while the opposite escape-apertureis simultaneously closed, thereby causin gall the brakes to be liftedoff. As it is not expedient to employ the full boiler-pressure forworking the lifter, I propose to reduce the said pressure to the desiredamount by causing the steam to pass through the peculiarpressure-regulator, of which Fig. 7 isa sectional elevation. Thisimproved pressure-regulator consists of a cylinder, A, of uniform bore,having two equalsized pistons, B B, working steam-tight therein, andbeing provided with two lateral openings, c c', situate between the twopistons. The opening c communicates -with the pipe C leading direct fromthe boiler, and the other opening, c, communicates with the pipe Cleading to the branch C of the three-way cock, Fig. 6, last described.From the opening or branch c a lateral branch passage, d, leads to theunder side of the bottom piston. On the top piston rests a spindle, D,which is pressed down by a helical spring, E. The steam, on its firstentering between the pistons, exerts an equal pressure on both; but, asa portion of the steam finds its wayjby the passage d underneath thebottom piston, the equilibrium is destroyed and the pistons are elevatedmore or Vless against the pressure of the spring. This elevation of thepistons closes more or less the orifice c, and, by wire-drawing thesteam at that point reduces its pressure before it enters the three-waycock, Fig. 6, which directs it to the lifter. Should the pressure in theboiler increase, then the pistons will be still further raised againstthe pressure of the spring and the oriiice at c still furtherreduced'until the resistance of the spring balances the extra pressureof thc steam under the bottom of the lower piston. Should the pressurein the boiler fall, th en the spring will depress the pistons andincrease the opening at c, thus maintaining in the cylinders of thelifter a nearly uniform pressure, which never exceeds that which isnecessary for the efficient working of the apparatus. The continuousrope or chain G is composed of several lengths coupled together, eachcarriage containing its own portion. Fig. 8 represents a peculiarconstruction of links for facilitating` the coupling and uncoupling ofthe several lengths of rope or chain in each carriage when making up atrain, the several lengths when coupled up constituting the continuousrope or chain before referred to. These links are cut through on oneside, and have their adjoining ends beveled to a knife or V edge, asshown at a, and as both 'the links are precisely the same it is simplynecessary, in order to couple or uncouple them, to bring the cut ordivided portion of one link at right angles or crosswise to the other,so that the V-ends of one link will t into the V-recesses on theopposite sides of the other shorter arm, while the continuous rope orchain G, after passing round a guide-pulley, is connected to the largerarm. Owing to the action of the bent lever the spring will exert auniform or nearly uniform tension on the chain in whatever positionthelever may be drawn; or a weight slightly exceeding the force required onthe continuous rope or chain may be suspended at the end thereof; orbell-crank or other levers, A and B, Fig. 10, may be connected by onearm to the draw-bars C, or to the buffer-rods D, While the other armcarries a pulley, E, which, by diverting more or less the continuouschain G from a right line, will cause it to vary in length, as may berequired; or a spring may be employed, iixed at one end and at the otherconnected to a pulley pressing on the chain or rope, the normal positionof which being slightly out of a right line any undue strain will causethe pulley to push back the spring and thus relieve the chain.

Although I have had occasion herein to describeseveraldistinctmechanicalcontrivances, 'each embodying its own improvements, yet they are allintended to be employed in cornbination and constitute one system ofbrake mechanism.

Having now described my invention, I would observe that what I claimis- 1. The combination of springM, toggle-links H, and brake-lever Dwith the pulley E, continuous rope or chain G, and brakes S S', allarranged and operating together substantially in the manner and for thepurpose hereinbcfore described.

2. rlhe peculiar combination of cylinders A, pistons B, cross-head D,pulleys F and H, and cushion-valve M, arranged and operating togethersubstantially in the manner and for the purpose hereinbefore described.

3. The peculiar construction and arrangement of pressure-regulator,consisting of the cylinder A, of uniform bore throughout, theequal-sized pistons B, spring' E, lateral passage d, and apertures c andc', operating substantially as and for the purpose hereinbeforedescribed.

4. The peculiar construction of couplinglinks, as hereinbeforedescribed, and illustrated by Fig. 8 of my drawing.

5. The peculiar arrangements for taking up the slack of the continuousrope or chain, and for preventing the same from being subjected to unduestrains, as hereinbefore described.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

WILLIAM .NAYLOR Witnesses: y

WM. LYsTEn HoLT, 7 Great Winchester St Build/ings, London. FRED.WALKDEN, 47 Lincolns Inn Ft'elds, London.

